OBJECTIVE: 1. Radiotherapy release of tumor specific antigen in serum and its effect on the nature of host immune response to the tumor. Objective is to quantitate increased levels of tumor specific antigen in serum following local radiation of rat and mouse fibrosarcomata, measured by spleen cell migration inhibition, indirect immunofluorescence and immunodiffusion of sera. 2. Influence of nonspecific immune adjuvants BCG and C. Parvum on experimental radiation therapy of solid tumors by measuring tumor growth rate and host survival. Determine if a metastasizing rat epithelioma responds to combined radiotherapy and immune stimulation with reduced metastases. Verify previously found resistance to metastases in rats cured by radiation plus immune adjuvant. 3. Polycations as cytophilic factor binding mouse peritoneal macrophages to tumor cells. Objective is to determine if polycations increase efficiency of cytolysis of fibrosarcoma tumor cells, determined by colony inhibition and 125IUdR release assays. 4. Wish to study nature of cytotoxic cells by development of nonspecific killer lymphocytes in rat thoracic duct lymph following early drainage. Have observed that rat lymphocytes after 8-12 hours of lymph drainage become killer cells, using in vitro cell cytoxicity technique. Will separate small lymphocytes, blast cells, B-and T-cells. Influence of radiation during drainage on cytotoxicity of immune lymphocytes.